Easy Rainbow Bundt Cake

This Rainbow Bundt Cake may look complicated but trust me, anyone can make it! Simple to make with a doctored up cake mix recipe and gel food coloring to make the prettiest rainbow layers. It’s the perfect cake to make for St. Patrick’s Day dessert or any rainbow themed party. 

For more rainbow treats be sure and try my Rainbow Rice Krispie Treats or this Lucky Charms Rainbow Snack Mix.

Rainbow Bundt Cake (Easy Cake Mix + Instant Pudding Cake Recipe)

Don’t let this easy cake mix rainbow bundt cake fool you… it tastes like it came straight from a bakery! It bakes up perfectly inside a bundt cake pan with 7 layers of rainbow colors with red, orange, yellow, green, blue, and purple.

Top it off with an easy powdered sugar + heavy cream vanilla glaze and you have an impressive looking and totally delicious rainbow dessert. My family was eating it days later and it was just as moist and yummy as the day we made it!

Ingredients Needed

• Easy Rainbow Bundt Cake Ingredients

  • Vanilla Cake Mix – You can also use a white cake mix but I prefer the flavor of the vanilla over the white cake mix. 
  • Vanilla Instant Pudding – No need to prepare this beforehand. Just dump in the dry contents from the package. You and also use a box of instant white chocolate pudding mix if you’re using a white cake mix. 
  • Full-Fat Sour Cream
  • Vegetable or Canola Oil
  • Large Eggs – 4 eggs provides tons of richness and moisture when combined with the other ingredients. 
  • Evaporated Milk – Just a small 5 ounce can is what you need. 
  • Gel Food Coloring – It’s best to use gel food coloring because you need less of it to create vibrant colors (when compared with the liquid food coloring). You can find a box of gel food dye with red, blue, yellow, and green and then there is also a neon version that will contain orange and purple in it. Those can be found in the baking aisle. You can also use the small containers of gel food coloring that can be found in the cake decorating aisle or at any craft store. 

• Vanilla Glaze

  • Powdered Sugar
  • Heavy Cream
  • Vanilla Extract
  • Rainbow Sprinkles 

How To Make a Rainbow Bundt Cake

This cake may look like it’s complicated and hard to make, but trust me, anyone can make it! I’ll show you how with the simple steps below. Be sure and read to the bottom of the page where there is a detailed recipe card, a printable option, and a pin it button so you can save this recipe for later. 

• Prep : Heat the oven to 350 degrees. Grease a bundt pan with shortening or butter and then add flour. Tap the bundt pan to move the flour around to coat all the shortening. 
• Cake Batter : Using a hand mixer, beat together all the rainbow cake ingredients on medium speed for at least 1-2 minutes. Use a spatula to scrape the sides and bottom of the bowl as necessary. 
• Colored Cake Batter Bowls : Divide the cake batter between 6 smaller bowls. Add 2-4 drops of gel food coloring, one color per bowl, and stir until it’s well combined. 
• Make The Rainbow Layers : Start with the red and pour it into the bottom of the bundt pan. Next is the orange, pour it directly on top of the red batter trying to not mix the two colors at all. Continue on with the yellow, green, blue, and purple following the same guidelines. 
• Bake : Cook for 35-45 minutes or until a toothpick inserted into the center comes out clean.
• Cool & Rest : Allow the Bundt Cake to cool inside the warm pan for 15 minutes before inverting it onto a cooling rack. Let it cool completely before frosting it. 
• Glaze : Prepare the glaze and pour it over the Bundt Cake and then immediately decorate with rainbow sprinkles. 

Rainbow Bundt Cake FAQ’s

• What Other Cake Mix + Pudding Mix Combinations Can I Use?

  • It’s important that the base of the cake is as white or close to white as can be so the rainbow layers and color can show through. There are really only 2 combinations that would work well for this recipe. 
    • Vanilla Cake Mix + Vanilla Instant Pudding Mix
    • White Cake Mix + White Chocolate Instant Pudding Mix

• Serving Suggestions

  • Whipped Cream Clouds : Instead of making the glaze for the cake try serving the cake as is with big whipped cream clouds at the ends of the slice. Sprinkle on some rainbow sprinkles (on the clouds) for decoration. 
  • Gold Wrapped Rolo Candy : Serve each slice with a gold wrapped Rolo candy for a golden treasure at the end of the rainbow. 
  • Vanilla Ice Cream : Serve the cake with a scoop of vanilla ice cream for the ‘clouds’.

• How To Store Leftover Bundt Cake

  • Make sure that leftovers are stored tightly, in an airtight container or wrapped well in plastic wrap, at room temperature for up to 4-5 days. 
  • If you are storing the bundt cake with the glaze on it you will need to store the leftovers in the fridge instead. 

• Variation Ideas

  • Holidays : You can create this bundt cake for any Holiday using any colors that you want. You don’t even have to do the 6 different colored layers, just do 2-4 and only divide the batter between the number of layers you want. Do a green layer, red layer, and a white layer for Christmas. Or a pink layer, red layer, and white layer for Valentine’s Day. Try pastel colored layers for Easter. Do a white layer, orange layer, and yellow layer for a candy corn inspired cake for halloween. 
  • Frosting or Glaze : If you have a recipe for a cream cheese frosting or buttercream frosting, feel free to use whatever frosting or glaze you want for the top of this cake. You can even make it real simple and use a can of pre-made store-bought white frosting and drizzle that over the cake. You will probably want to warm it up a bit in the microwave to get it at pourable consistency. 
  • Sprinkles : Use anything you love here to top off this rainbow bundt cake with. Try using rainbow colored skittles, any variation of sprinkles, chopped rainbow sour candy, chopped candy bars, or try doing a rainbow drizzle with different colors of melted candy melts. 

Recipe Tips

Here are a few of my helpful tips so that you can have success recreating this recipe in your own kitchen ♥

• Don’t Skip Shortening + Flour : It’s so important that you don’t skip this! You might think it’s not a big deal, but it is. When I tested this recipe with just cooking spray inside the bundt pan, the exterior of the cake came out very dark, browned, and with a crispy texture to it. Cooking spray can sometimes make the parts of the cake that touch it very crispy and overly browned (which is like all over with a bundt pan). This is the reason you must use shortening and flour to prevent the cake from sticking. It will make a huge difference. Promise!
• Use Gel Food Coloring : Gel food coloring is preferred because you don’t have to use as much of it (compared to the liquid food dye) to achieve a bright and vibrant color. Especially with the color red. Using the liquid dye can add a lot more liquid to the cake batter which is not always a good thing. The colors also bake up more vibrant when using gel food dye. 
• Toothpick Trick : Make sure you have toothpicks handy because it’s the best way to test for doneness when making this cake. Stick a toothpick into the center of the cake (from the top of the bundt pan) and if it comes out with wet batter then it’s not done. If it comes out dry or with moist crumbs then you’re good to go. 
• Cooled Cake Before Frosting : Make sure the cake is completely cooled to room temperature before adding the glaze over top. If the cake is too warm, the glaze will just fall right off and you won’t get that white glaze to adhere to the cake. 

More Funfetti & Rainbow Recipes You’ll Love

• Funfetti Cake Batter Cookie Bars – You’ll be amazed at what a cake mix + a cookie mix create with this fun rainbow confetti recipe. 
• Funfetti Chex Mix – Like muddy buddies but with rainbow sprinkles!
• Easy Funfetti Donuts – Starts with a cake mix. Top it off with rainbow sprinkles. 
• Rainbow Jello Poke Cake – A fun twist to the classic jello poke cake with rainbow colors. 
• Rainbow Popcorn – Uses jello powder to create this fun popcorn snack. 
• Froot Loop Cereal Marshmallow Bars – Froot Loops cereal are already a fun rainbow color which makes them perfect for rainbow recipes.